Multi-mode Airborne Digital Camera System (MADC) is a novel airborne digital camera developed by Institute of Remote Sensing Applications of Chinese Academy of Sciences. The image acquisition and processing of MADC system and its application in the mapping and application of city ortho-image are introduced in the paper. The Jining city in Shandong province was taken as an example for the application and analysis. Sever primary data processing algorithms correlating of MADC system have been introduced in the paper, mainly involved: the algorithm of camera lens distortion and proofreading method, the algorithm which effects the image because of terrain undulation and the algorithm of ortho-image generation. The work flow is proposed for image processing and ortho-image generation using MADC image data. At the end, some suggestions are put forward for improving the performance of MADC system and increasing its application in city remote sensing.